Lettuce Gives Off Three Times More Greenhouse Gas Than Bacon – Researchers

A paper published in the journal Environmental Systems and Decisions revealed that lettuce emits more greenhouse gas emissions than bacon, and this underscores the fact that a vegetarian diet has little or no impact on the environment, according to the Scientific American.

The research was conducted by researchers from Carnegie Mellon University, and it establishes the fact the 2010 dietary recommendations offered by the Department of Agriculture would produce 38% higher energy use, 10% rise in water use, and 6% increase in greenhouse gas emissions – if Americans would change to diets that the Agriculture Department wants.

The guidelines prescribed by the USDA provides that vegetables, seafood, dairy, and fruits among other per-calorie based foods are much better than fats and processed sugary foods; and this underscores the research that lettuce emits three times more greenhouse gas than bacon.

"You cannot just jump and assume that any vegetarian diet is going to have a low impact on the environment," said Paul Fischbeck, professor of social and decision sciences and engineering and public policy. "There are many that do, but not all. You can't treat all fruits and veggies as good for the environment."

The scientists were able to run a series of tests in the course of their analysis to determine the levels of water and energy use in order to know the amount of emissions each of them give off into the environment. Over 100 foods were tested in this way via meta-analysis. Ultimately it was discovered that fruits posses the largest amounts of energy and water calories, while beef and seafood emit more greenhouse gas in terms of calories.

The researchers in part relied on data created by the US Centers for Disease Control and Prevention (CDC) in measuring the levels of calories individuals require to achieve average weight, and this is what is most suitable for most American adults.

"If what your concern is the greenhouse gas emissions or energy or water use of the entire system, I don't think you should leave out large chunks of it," Fischbeck said. "If you want to know how much energy is being consumed, you have to include waste and what is lost from grocery store or dining room table."

Then he adds that while most vegetables are good, some such as carrots, okra, onions, brussel sprouts and broccoli are capable of emitting greenhouse gases that impact the environment. Since lettuce needs much energy and water to grow, harvesting and transporting is an issue. "I would eat less lettuce and more Brussels sprouts," he added.